This is the slack-jawed question for Julie Zhou when friends learn that, after turning off the lights at Yik Yak’s West Coast office, she hits the gym and pumps 240 lbs. of pure iron. But Julie weighs in at just over 100 lbs. How can she lift something at that scale?

Her answer, as it turns out, is fairly rote and unexciting: “Every single week, you lift one amount. Next week, you add five more pounds. Then, you add five more.”

And yet there may be a deceptive genius here. Deadlifter by night, Julie effects a similar magic in her work life. She helps startups get swole.

Currently, Julie is heading up Growth at Yik Yak, a location-based social network that is mega-popular on college campuses. Before that, she was Growthmaster at Hipmunk and had worked in product marketing at Google. She teaches at General Assembly, mentors at 500 Startups, and is putting together a “practical guide” on the topic.

“I’m someone who’s lived it and breathed it and been in the trenches,” Julie says.

And out of the trenches, she’s returned with wisdom. But it’s not for the faint of heart.

Do you even “growth hack?”

Julie’s first trench was Google. She had joined the juggernaut’s Product Marketing organization. While it wasn’t exactly Growth, it taught her some things, like how to win attention inside of the engineering-driven machine.

“Anything marketing wanted to do had to be backed up with data,” she says. “It had to always have some quantitative justification around why company resources should be spent on those efforts versus anything else.”

One of the major projects Julie took on at Google was text ads, an undertaking she at first mischaracterized as “un-exciting.” But after looking into the data behind text ads, Julie realized just how much power was at her disposal. On Forbes, Julie wrote: “On a canvas of 95 text characters, tiny changes had massive effects –clever capitalization and site links increased engagement rate by three or four times.”

Her team was then able to transfer these learnings into larger channels, such as display and video.

“The first four years of my career were just boot camp data-driven marketing as a science.”

To continue growing herself, all she needed was to have the massive budget vanish.

Spotting

Today, Hipmunk has a solid reputation as a travel booking site. But when Julie joined the startup, there were only nine employees.

“I did not have nearly the budget I did at Google,” she recalls. “In fact, I had very, very little budget and quickly realized that was no way for Hipmunk to grow. Our resources as far as paid advertising were way too small to make a large impact. So I started looking for other ways to grow.”

Minor product tweaks, of the sort Julie had specialized in at Google, didn’t seem likely to improve Hipmunk. The company had already developed a great product. It just couldn’t rely on traditional paid growth channels, which were dominated by competition with far deeper pockets. Increasingly, it became clear that hacking growth would mean tapping into channels vs. product.

“Analytics is more important the scarcer your resources are.”

Luckily, they had done the math.

“Analytics is more important the scarcer your resources are,” Julie says.

Users who got on-app actually liked Hipmunk. In this case, the app’s gatekeepers were the sellers. After their iOS app had been featured in the “New and Noteworthy” section of Apple’s App Store, it experienced strong adoption. In comparison, Android adoption was at a standstill, but not for any difference in quality.

The approach had to be more classically biz dev. But unlike a lot of biz dev, it had to be on the cheaper end.Julie calls these kinds of partnerships “atomic bonding.” Atomic bonding means finding a way to link a larger partner’s success to your own. For Android, the partnership she wanted to cinch was Google.

So commenced a full-court press of emails and LinkedIn messages to old colleagues. Julie wanted to figure out who she needed to talk to at her former employer. Eventually, she learned that to be front-and-center on the Google Play store, she needed to woo a department deep within Google: Developer Relations.

Going before Developer Relations, they asked a simple question: What could Hipmunk do to convince Developer Relations of the strength of their app?

Developer Relations presented them with a challenge.

Google I/O was fast-approaching and the Nexus 7, a new tablet, would be premiering there. The Nexus 7 had its own crowd to please. It needed to appear handsome with a suite of design-savvy apps. If they so chose, Hipmunk could try to win Google’s favor by optimizing its Android app for the tablet and in accordance with Google’s newest design guidelines.

There’s a certain hustle to what Julie Zhou does. Here, her to-do list changed with the rules of engagement. So when Google said two weeks, that became Hipmunk’s calendar. And despite forging the relationship, Julie delegated its execution to her developer. She had to hedge on other players and circumstances.

“Growth is everyone’s responsibility,” she says. “It’s not just the role of marketing, it’s the role of the entire company and every single department needs to be involved.”

The powers at Google decided to feature Hipmunk on the Play store. It was quid pro quo, no money exchanged. After I/O, Hipmunk’s daily active Android users skyrocketed.

Still, it’d be foolish to think of this strategy as something turnkey. It’d be more foolish yet to think of it as an endorsement of “It’s who you know.”

Julie’s growth effort required analytics upfront to acknowledge where Hipmunk was prospering. It identified how past successes could be replicated in new relationships. Research granted them access to the right decision makers within the leviathan. Julie and Hipmunk had to make a promise to prove their value. Finally, Julie entrusted a department outside of her own to deliver.

If Julie had pigeonholed herself in product tweaks, the Android app would still be in some deep layer of the Google Play store. Instead, she recognized what the app needed to grow in particular.

Where does growth belong?

Moving on to Yik Yak meant Julie rethinking her skill set. Social apps fill a different role in users’ lives than a retail site.

“There are many companies that are small enough or have strong enough vision that growth can be shared among a lot of different orgs,” Julie says. “Invariably, departments start siloing themselves and losing the big picture as companies get bigger. At that point, it’s worth creating a central growth effort. Many companies do it differently. Some have growth living within product. Others have growth living within marketing. Other companies still have growth as its own org that has its own marketing and engineering design and analytics team.”

At Hipmunk, growth opportunities came from top-of-the-funnel. But Yik Yak’s growth opportunities occurred after a user had already landed on app. As a result, the majority of growth initiatives from within the product team.

Getting Yik Yak in front of users was a non-question. Retention was the focus. But before making hard and fast decisions, Julie had to run some tests.

One experiment at Yik Yak was around re-engagement notifications. If Yik Yak told its less engaged users they were missing their school’s feed, would they feel the FOMO?

“We had a targeted group and control group, and we carefully measured the return rate for the targeted versus the control group because there were some people who would come back anyway,” Julie says. “There was a massive difference immediately in the targeted users versus the control users. But that was somewhat to be expected if you get a notification.”

It turned out notifications were an effective way to herd yaks. They not only brought users back, but saw them returning with regularity. The task was now to make this data actionable.

Knowing this behavior, you could try and manage users’ lifecycles more closely with a volume of notifications or personalized notifications. You could also could try both, measure which is more effective, and select from there.

One may prove stronger in the long-term. For a hot startup like Yik Yak, keeping return behavior strong may be the rule of engagement now, but the tactics will have to change over time.

“Yik Yak is very, very strong in the college community, but we want to be equally as strong when our current users graduate and go to cities,” Julie says. “There, the metrics become different.”

Today’s growtherati need to know more than how to transition from one type of company to another. They need to grow their skillsets as the DNA of their company changes.

240 lbs.

Julie’s career so far has been a crash course in growth hacking, but that doesn’t mean it provides a template.

Growth can be a slog. Her advice for growth hacking is similar to her advice for deadlifting over twice your weight: If you want to surmount massive problems at scale, a combination of different exercises over time is the surest key to success.

But she cautions: “It’s very boring. It’s not like I did this and suddenly became strong.”

Rather, the process of weightlifting is quantitative. It’s iterative. It requires that she frequently run tests and track progress according to those.

“With weightlifting, it’s very easy to tell when you’ve made progress. There’s a higher number that you write down in a spreadsheet. It’s very, very applicable to growth. I’m very much a motivation-by-progress person. Here’s the KPI that I want to have by the end of the quarter. Let’s just track how we’re doing every week.”

So, Julie marches in to Yik Yak’s West Coast office and flips the lights on. She asks herself: “Are we better or worse off than we were last week?”

Published by Susan Su

Susan is a partner on the 500 Startups Distribution Team, specializing in content and email marketing. She has previously run marketing and growth for Inside Network (acquired byWebMediaBrands in 2011), AppSumo.com, and Ramit Sethi.